A new approach to estimate plastic region near tunnel considering excavation induced damage and in situ rock mass condition

摘要

An approach for the estimation of the radius of plastic region and the stress distribution in elastic and plastic regions near tunnel is proposed. Together with elasticity of cylindrical opening and Hoek-Brown 2002 criterion, the radius of plastic zone and stress distribution around a tunnel can be estimated. In addition, the use of Hoek-Brown 2002 criterion provides the application of the damage induced during construction and the characteristics of in situ rock mass condition. The results from the proposition show increase of the radius of plastic zone and decrease of the peak tangential stress as rock quality becomes poor.